Horizontally adjustable armrests for wheelchairs

ABSTRACT

A horizontally adjustable armrest assembly for invalid wheelchairs incorporating mechanism for selectively positioning the armrest to facilitate ingress or egress and positioning of the wheelchair relative to a table, desk, or the like.

Unite States Patent [1 1 Limpach [111 3,767,260 Oct. 23, 1973HORIZONTALLY ADJUSTABLE ARMRESTS FOR WHEELCHAIRS [75] lnventor: ,Paul D.Limpach, Napoleon, Ohio [73] Assignee: Gendron-Diemer, lnc., Archbold,

Ohio

[22] Filed: Aug. 20, 1971 21 Appl. No.: 173,410

I52] US. Cl 297/417, 297/422, 297/DlG. 4 [51] Int. Cl A47c 7/54 [58]Field of Search 297/4l7, DIG. 4,

[56] References Cited UNITED STATES PATENTS 3,376,066 Kernes 297 417Pivacek 297/422 Presty 297/DlG. 4

Primary ExaminerJames T. McCall Att0rney-Wilson & Fraser [57] ABSTRACT Ahorizontally adjustable armrest assembly for invalid wheelchairsincorporating mechanism for selectively positioning the armrest tofacilitate ingress or egress and positioning of the wheelchair relativeto a table, desk, or the like.

8 Claims, 3 Drawing Figures PAIENIEflucrzams INVENTOR. PAUL D. L IMPACHATTORNEYS HORIZONTALLY ADJUSTABLE ARMRESTS FOR WHEELCHAIRS BACKGROUND OFTHEINVENTION Heretofore, it has been known that changing the profile ofan armrest portion of a wheelchair enables the wheelchair to bepositioned closely adjacent to a desk or table, and that moving thearmrest assembly to a rearward position provides ready ingress or egressto the user of the wheelchair.

Some of the problems associated with the designs of the prior artinclude the requirement of complex and difficult motions on the part ofthe user where the armrest frame assembly is removable from theobstruction position and must be equipped with plungers and similarsecuring means to provide adequate locking means for the armrestassembly. Where the motions required have been simple, the design hasbeen such that only the armrest or arm cushion means moves relative tothe frame assembly. Further, the designs, where the frame assembly canbe moved to a non-obstructive position, have relied on support andguidance from attachments to the framework of the back portion of thewheelchair which could not be employed in wheelchair structures whereinthe back support is reclinable. The combining of the armrest mechanismwith the pusher tube of the wheelchair gives rise to the possibilityofunnecessary stresses being applied to the mechanism by the pusher tubein moving the wheelchair. In some instances, the securing means'for thepositioning mechanism of the armrest assembly is dependent on theexactness 'of alignment which can be applied to the securing means forsecuring the position of the assembly, such as aligning plungers withassociated holes. The present armrest assembly overcomes the aboveproblems by providing a slidable armrest assembly supported from aposition below the level of the wheelchair seat and operable by a singlelatching mechanism responsive to finger pressure and provides forselective positioning of the armrest assembly relative to th wheelchairframe assembly.

SUMMARY The present invention relates to wheelchairs and moreparticularly to horizontally adjustable armrests for wheelchairs. Awheelchair in accordance with the present invention may have a pair ofspaced apart side frame members interconnected by a suitably disposedX-frame. Generally, an invalid supporting seat structure is affixed toextend between the side frame members. Each of the side frame membersincludes vertically extending front and rear tubes having a horizontallydisposed member extending therebetween. The horizontally disposed memberis positioned below the elevation of the wheelchair seat. An armrestassembly is slidably connected to the horizontally disposed member andmay include a tube telescopingly received within the horizontallydisposed tube.

The armrest assembly can be slidably advanced to a forward position forarm support or retracted to a rearward position to remove theobstruction presented by the armrest assembly above the elevation of thesupport means for the seat to thereby facilitate lateral movement of theuser.

Extreme and intermediate positions of the armrest frame may beestablished by means for selectively positioning the armrest assemblysuch as latch means which may include a pivotal lever attached theretohaving notches for engaging a detent on the horizontally disposed tube.Upward movement of the lever disengages the notches allowing movement ofthe armrest frame.

The lever returns by the force of gravity to a position of engagementbetween the latch and any notch passing thereover.

The present armrest frame assembly is a simplification in design andoperation over the piror art armrests. Simplification of design resultsin a rugged mechanism of lower cost because of its more economicalmanufacture.

BRIEF DESCRIPTION OF THE DRAWINGS The other objects and advantages ofthe invention will become readily apparent from reading the followingdetailed description of an embodiment of the invention when consideredin the light of the accompanying drawings, in which:

FIG. 1 is a perspective view of the wheelchair assembly incorporatingthe features of the invention;

FIG. 2 is an enlarged fragmentary perspective view of the side of thewheelchair assembly illustrated in FIG. 1; and

FIG. 3 is an enlarged fragmentary sectional view of the wheelchairillustrated in FIG. 2 taken along line 3-3 thereof.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIGS. 1 through 3,the wheelchair consists primarily of two laterally spaced substantiallyidentical side frames A and B, an interconnecting seat 10, and abackrest 12. Each of the side frames A and B includes a front verticallydisposed rail or tube 14 affixed to a forward portion of a horizontalbase tube 16. Mounted on the extremity of the forward portion of thebase tube 16 is a caster wheel supporting cylinder 18 from which a frontcaster wheel 20 depends. At the rear of each of the side frames A and Bis a vertically disposed rear rail or tube 22 on which a large or drivewheel 24 is mounted.

V The two side frames A and B are collapsibly or foldably connected toone another by X-brace members 26 and 28. The X-brace members 26 and 28are pivotally interconnected at 30 and have their upper ends affixed tothe upper portion of one of the respective side frames on support tube32 while their lower ends are pivotally connected to the lower ends ofone of the respective side frames on the base tube 16. The lower ends ofthe X-brace members 26 and 28 are pivotally connected to the base tube16 of the respective side frames A and B. The support rail or tube 32extends longitudinally beneath the level of the seat 10 and extendsdownwardly at its forward position to attach to the caster wheelsupporting cylinder 18. The seat portion 10 is suspended between twospaced apart seat tubes 36 which may be secured to the respectivesupport tubes 32 by an upwardly extending support bracket 34. The rearportion of the seat tubes 36 are similarly secured to the support tubes32 by brackets, not shown.

The backrest 12 is suspended between two spaced apart pusher tubes 38,the lower ends of which are pivotally mounted with the respective sideframes A and B so that the backrest 12 may be selectively moved betweena sitting position and a reclining position. It will be noted that theuppermost free ends of the pusher tubes 38 are bent rearwardly toprovide handle parts to be grasped to trundle the wheelchair from placeto place. Where the wheel-chain is collapsible, preferrably, the seatand backrest 12 portions are formed of a flexible material.

in accordance with the invention, a horizontally adjustable armrestassembly is provided and consists essentially of an armrest frame 50 anda support member 44. The armrest. frame 50 includes an upperhorizontally disposed portion 40, a vertical frame portion 46 extendingfrom the front of the portion 40, a vertical frame portion 48 extendingfrom the rear of the portion 40, and slide rod 52 secured to thevertical portion 48 and adapted to extend forwardly in a cantileveredfash ion. The upper surface of the slide rod 52 is slightly lower thanthe free lower end of the vertical portion 46. A guide means 54 in theshape of a saddle is affixed to the free end of the portion 46.

The support member 44 for the armrest frame 50 is hollow and is disposedat or below the elevation of the seat tube 36 supporting the seat 10.The horizontally disposed member 44 is adapted to slidably receive theslide rod 52. To militate against relative rotation of the telescopingslide-rod 52 and the horizontally disposed member 44, the members arepreferrably formed with mating polygonal cross-sections, as illustratedin FIG. 3. Lubricating pad means 63, formed of teflon, for example, maybe inserted between the inner surface of the telescoping element 44 andthe outer surface of the slide rod 52. The use of such lubricating meansprovides for smooth movement between the telescoping members 44 and 52and results in quieter operation.

The saddle 54 is slidable with respect to the outer surface of thehorizontally disposed member 44 and guides the forward portion of thearmrest frame 50 during its travel. Both the telescoping tube 52 and thesaddle 54 provide firm support for the armrest frame 50 by bearingagainst the horizontally disposed member 44 which in turn extendsbetween and is securely affixed to the side frame members 14 and 22.Sleeves 64 may be welded or otherwise suitably secured to thehorizontally disposed member 44 and associated yoke member 66 may bewelded to members 14 and 22. The sleeves 64 are fastened to the yokes 66as at 68, to achieve the above connection between the respective sideframe and the member 44. By supporting the armrest assembly completelyfrom below the elevation of the support tube 36 of the seat 10 in aslidable manner, the armrest frame 50 may be retracted from theintermediate position illustrated to a position C (in phantom) where theentire side of the wheelchair above the elevation of the seat 10 isclear for lateral movement of the user. Also such support mechanismfrees the backrest 12 for pivotal movement. When the armrest frame 50 isadvanced to a position D, illustrated in phantom, full arm support isgiven. In intermediate positions, the armrest frame 50 may be adjustedto position the user in close proximity to a table, desk, etc. Attachedto thearmrest frame 50 is an enclosure panel 56 affixed to rods 58 whichare fastened to the frame 50 by suitable threaded fasteners 60 andinserted in apertures in the frame 50 at 62..

It is to be understood that other means for slidably connecting thearmrest frame 50 to the horizontally disposed member 44 other thantelescoping elements and a slidable saddle may be used. For example,slidable channels and a depending element from the armrest frame 50engaging the slot in the channels.

To secure the armrest frame 50 in a desired position, means forslectively positioning the armrest frame 50 can be provided in the formof a detent attached to the horizontally disposed member 44 in aconvenient manner, such as a threaded fastener 68. The detent 70 isengageable by notches 72 formed in a lever 74 pivotally attached to thearmrest frame 50 as at 76. Opposite the pivotal end of the lever 74, atab portion 78 is formed by offsetting the end laterally to position thetab 78 in a convenient location for the user along side the frame member46. Finger pressure on the tab 78 in the direction of the arrow F inFIG. 2 causes the lever 74 to pivot and release the notch 72 from thepositive engagement with the detent 70. The single motion of lifting thelever 74 allows the armrest frame 50 to be moved in either forward orbackward movement. Once the lever is disengaged, the tab 78 can bereleased and the force of gravity will cause the positive engagementbetween the detent 70 and any notch 72 passing thereunder. The number ofnotches 72 required and their location are determined by the number andlocation of the armrest frame 50 positions desired.

Limitation of the overall travel of the armrest frame 50 to preventdisengagement from an associated side frame may be accomplished by'mounting a protusion, such as a pin 80, in a position on thetelescoping tube 52 to engage the rearward end of the horizontallydisposed member 44 when the armrest frame 50 is in the forwardmostposition providing a forward stop. A rear stop is provided by the detent70 on the horizontally disposed member 44 to engage the saddle 54 in aposition corresponding to the rearward most position of the armrestframe 50.

It will be noted that the tab 78 in its position along side thevertically extending frame portion 46 militates against movement of thelever 74 inwardly of the wheelchair. A pin 82 extending upwardly fromthe detent 70, as clearly illustrated in FIGS. 2 and 3, militatesagainst movement of the lever 74 outwardly of the wheelchair. Coactionof the tab 78 and pin 82 in the above manner maintains the lateralalignment of the lever 74.

The forward movement of the armrest frame 50 could be varied by causingthe detent 70 to be movably positioned along the length of thehorizontally disposed member 44 thereby adjusting the location ofengagement between the detent 70 and the notches 72 on the lever '74.

The present horizontally adjustable armrest frame assembly is one ofsimple design and operation. Operation of the positioning means isconvenient for the user and requires only a single motion foractivation. The simple design of only a few number of components resultsin a rugged device which is economically manufactured.

In accordance with the provisions of the patent statutes l haveexplained the principles and mode of operation of my invention and haveillustrated and described what I now consider to represent its bestembodiment. However, I desire to have it understood that the inventionmay be practiced otherwise than as specifically illustrated anddescribed without departing from its spirit or scope.

I claim:

l. A wheelchair having a seat and means for supporting said seat; a pairof spaced apart side frame members, each of said frame members includinga vertically disposed front tube and a rearwardly spaced verticallyextending rear tube; the improvement comprising:

a horizontally adjustable armrest assembly said arm rest assemblyconsisting of an armrest frame and a horizontally disposed memberextending between said front and rear vertically disposed tubes at alevel which does not extend above the elevation of said means forsupporting said seat;

means slidably connecting said armrest frame to said horizontallydisposed member, at least a portion of said armrest frame disposed atsubstantially elbow height when a user is seated in said wheelchairwhereby said armrest frame may be slidably advanced to a forwardposition for arm support or remeans slidably connecting said armrestframe to said horizontally disposed member includes a tube telescopinglyreceived within said horizontally disposed member.

3. The invention defined in claim 2 wherein said horizontally disposedmember and said telescoping tube having mating polygonal cross-sections.

4. The invention defined in claim 1 wherein said means slidablyconnecting said armrest frame to said horizontally disposed memberincludes guide means slidable along a portion of the outer surface ofsaid horizontally disposed member.

5. The invention defined in claim 4 wherein said guide means includes asaddle straddling said horizontally disposed member.

6. The invention defined in claim 1 wherein said latching lever meansincludes a detent affixed to said horizontally disposed member forengagement with said notch on said lever.

7. The invention defined in claim 6 wherein said lever further includesat least one notch thereon for engaging said detent affixed to saidhorizontally disposed member.

8. The invention defined in claim 6 wherein said lever includes aplurality of notches extending along the length thereof for selectiveengagement with said detent affixed to said horizontally disposedmember.

1. A wheelchair having a seat and means for supporting said seat; a pairof spaced apart side frame members, each of said frame members includinga vertically disposed front tube and a rearwardly spaced verticallyextending rear tube; the improvement comprising: a horizontallyadjustable armrest assembly said armrest assembly consisting of anarmrest frame and a horizontally disposed member extending between saidfront and rear vertically disposed tubes at a level which does notextend above the elevation of said means for supporting said seat; meansslidably connecting said armrest frame to said horizontally disposedmember, at least a portion of said armrest frame disposed atsubstantially elbow height when a user is seated in said wheelchairwhereby said armrest frame may be slidably advanced to a forwardposition for arm support or retracted to a rearward position to removethe obstruction presented by said armrest frame assembly above theelevation of said means for supporting said seat thereby providing forlateral movement of the user; and latching lever means for positivelypositioning said armrest frame relative to said horizontally disposedmember, said lever means including a lever carried by said armrest frameand pivotally mounted to said armrest frame at one end thereof.
 2. Theinvention defined in claim 1 wherein said means slidably connecting saidarmrest frame to said horizontally disposed member includes a tubetelescopingly received within said horizontally disposed member.
 3. Theinvention defined in claim 2 wherein said horizontally disposed memberand said telescoping tube having mating polygonal cross-sections.
 4. Theinvention defined in claim 1 wherein said means slidably connecting saidarmrest frame to said horizontally disposed member includes guide meansslidable along a portion of the outer surface of said horizontallydisposed member.
 5. The invention defined in claim 4 wherein said guidemeans includes a saddle straddling said horizontally disposed member. 6.The invention defined in claim 1 wherein said latching lever meansincludes a detent affixed to sAid horizontally disposed member forengagement with said notch on said lever.
 7. The invention defined inclaim 6 wherein said lever further includes at least one notch thereonfor engaging said detent affixed to said horizontally disposed member.8. The invention defined in claim 6 wherein said lever includes aplurality of notches extending along the length thereof for selectiveengagement with said detent affixed to said horizontally disposedmember.